1. Field of the Invention
The present invention relates to a method for regenerating a photovoltaic module and a photovoltaic module. More specifically, the present invention relates to a method for regenerating a crystalline photovoltaic module having a super straight type structure in which a light-receiving surface side-sealing resin (EVA: ethylene vinyl acetate) layer, a photovoltaic cell, a back surface side-sealing resin (EVA) layer and a back surface side-sealing weatherproof film are laminated sequentially in this order on a light-receiving glass and these components are formed into an integral piece, and such a photovoltaic module.
2. Description of the Related Art
Photovoltaic modules have been developed and produced with weatherproofness, durability and reliability for long term operation as the first priority so that the photovoltaic modules can be used in exposed outdoor locations over a long time. For example, reliability tests of crystalline photovoltaic modules are defined in JIS C8917 or IEC61215, and manufacturers of photovoltaic modules have made efforts to satisfy the requirements of the tests and further have pursued for higher reliability with their own safety margins.
Photovoltaic modules for houses have been rapidly spread, partly because of the governmental aid for private houses that started in 1996 in Japan together with increased consciousness of environmental problems. This rapid spread has resulted from the efforts put to a market development by suppliers, which have make it possible to install a photovoltaic module with about 3 KW, which covers all power consumption of a standard household, on a roof of a house, and to develop a photovoltaic module whose appearance goes with the roof of a house and a method for installing the photovoltaic module.
On the other hand, industrial photovoltaic modules that are installed in buildings, warehouses, gymnastic halls, or large capacity public buildings have been remarkably spread. Power generating systems for the industrial field for buildings are attributed mostly to the demand creation of the NEDO field test projects that started in 1992 in Japan, and in recent years, industrial power generating systems developed by the private sector also have been started to be introduced. Their features are that unlike a power generation of about 3 KW for general households, the power generation scale is as large as 10 KW or more, and the area for installation is large.
In order to achieve the new energy introduction outline, the solar power generating system has been promoted energetically by both public and private sectors, as described above. However, the system has a lifetime as long as it is man-made equipment, so that eventually it is disposed of or recycled.
The solar power generating system is in the early stage of the introduction, and its life is long, so that there is little need of treatment after use. It is very important and necessary also in view of the nature as a commercial product to develop the technologies for disposal methods or the recycling properties of the photovoltaic modules in order to prepare for the future introduction in large quantity. However, it is difficult to disintegrate the photovoltaic module, and it is also true that if a material and a structure that allow the photovoltaic module to be disintegrated easily are used, long term reliability cannot be ensured. There is no clear definition as to a specific quantitative lifetime of the photovoltaic module.
In other words, unlike other electrical products, the photovoltaic module has a peculiarity in that it should continue to generate power, once it is installed. In recent years, the guarantee period of manufactures of the photovoltaic module is generally 10 years, but even if this period has passed, the photovoltaic module does not stop working. On the other hand, although it is desirable to select and collect the materials when the photovoltaic module has stopped generating electricity, the current state of the art cannot balance the cost and benefits, and therefore there is no other way but to dispose of the photovoltaic module as special industrial waste.
Thus, it is useful in terms of recycling and reuse to allow the photovoltaic module to generate power as long as possible, that is, to extend the lifetime of the photovoltaic module.